Potential Perils Born In Cloning

Risks Great Even In Animals, Researchers Say

March 04, 2001|By Jeremy Manier, Tribune Staff Writer.

Four years after Dolly the sheep became the first cloned mammal, scientists studying clones of numerous species are finding the animals have fundamental defects that could prove disastrous if the procedure is applied to humans.

Evidence on the risks of cloning is growing even as groups are laying the groundwork for cloning people. A team of American and Italian fertility researchers will meet in Rome this week to work on its plan to attempt the first human clone within the next year.

Although the U.S. Food and Drug Administration has banned such experiments, legal experts say the government has little power to stop private laboratories or clinics. Moreover, some scientists believe the public's revulsion with the concept of cloning has waned in the years since Dolly's creation--in fact, British lawmakers in January approved some cloning of human embryos for medical research.

But cloning is even harder than scientists thought. Many initial announcements of successful cloning experiments are being followed up by research showing severe problems down the line.

Findings suggest that the embryonic development of most clones is deeply flawed in ways that researchers have barely begun to understand. A leading explanation is that cloning from an adult cell throws off the delicate program of gene activation in a developing organism.

Despite years of efforts to perfect the process, most cloned animals still die in the womb. The ones that survive to birth often suffer from ultimately fatal defects of the heart, lungs, kidneys, brain or immune system.

"I doubt there are any normal clones whatsoever," said Rudolf Jaenisch, a professor of biology at the Massachusetts Institute of Technology and a leading expert on the developmental problems of clones.

Some studies suggest even the clone's surrogate mother faces potentially fatal risks from carrying clones, many of which are abnormally large at birth.

Such dangers pose little dilemma for biotechnology researchers who clone sheep, goats, cattle or mice, since they can abort or destroy defective animals.

But Ian Wilmut, the Scottish researcher whose team made Dolly, said it would be worse than careless to bring similarly defective human clones into the world.

"It would be criminally irresponsible to attempt to copy a person now," Wilmut said in an interview.

Public no longer shocked

Researchers working on cloning in animals said the dramatic failure rates have led most people in their field to oppose extending such work to humans. Yet that message may not have sunk in among the public or the fertility research teams that plan on cloning people, said Alexander Capron, a professor of law and medicine at the University of Southern California.

"Once the public has had time to digest something, there isn't the same level of amazement and disbelief," Capron said.

"It's ironic that we've actually had more indications from more species that there are problems, and yet people are talking about going forward with human clones."

Some corporate teams believe they have improved the cloning process in animals so that it carries fewer risks than early reports indicated. But even commercial researchers said the process is far from ripe for use in people.

"We're still very early in this field," said Robert Lanza, vice president of medical and scientific development at Worcester, Mass.-based Advanced Cell Technology Inc. "Cloning is as much an art as a science, and there's a lot we don't understand."

The mysteries run so deep that many scientists are studying animal clones as a window onto the basic mechanics of reproduction and embryonic growth.

But the insights spring largely from scrutiny of the lethal defects that most clones develop during gestation, said Mark Westhusin, a professor of veterinary physiology at Texas A&M University.

At least two groups hope to use that model to conjure cloned babies for infertile couples. One team led by researchers in Italy and Kentucky announced in January that it plans to try human cloning outside the U.S. within the next year.

A Canadian group that hopes to offer cloning services for $200,000 per couple draws its inspiration from a French-born mystic named Rael, who formed a religion based on the tenet that humans were created by aliens in a laboratory.

Unlikely as it seems, most experts said a determined team with enough volunteers could create cloned human embryos or even bring a child to term.

"They will produce clones, and most of those will die in utero," predicted MIT's Jaenisch. "Those are the lucky ones. Many of those that survive will have these abnormalities."

Fight for survival

Westhusin of Texas A&M has seen vivid evidence that the technology for safely cloning humans does not exist.